Question: Khan.scratchpad.disable(); To move up to the maestro level in her piano school, Tiffany needs to master at least $191$ songs. Tiffany has already mastered $46$ songs. If Tiffany can master $7$ songs per month, what is the minimum number of months it will take her to move to the maestro level?
To solve this, let's set up an expression to show how many songs Tiffany will have mastered after each month. Number of songs mastered $=$ $ $ Months at school $\times$ Songs mastered per month $+$ Songs already mastered Since Tiffany Needs to have at least $191$ songs mastered to move to maestro level, we can set up an inequality to find the number of months needed. Number of songs mastered $\geq 191$ Months at school $\times$ Songs mastered per month $ +$ Songs already mastered $\geq 191$ We are solving for the months spent at school, so let the number of months be represented by the variable $x$ We can now plug in: $x \cdot 7 + 46 \geq 191$ $ x \cdot 7 \geq 191 - 46 $ $ x \cdot 7 \geq 145 $ $x \geq \dfrac{145}{7} \approx 20.71$ Since we only care about whole months that Tiffany has spent working, we round $20.71$ up to $21$ Tiffany must work for at least 21 months.